Posted
by
samzenpus
on Thursday January 15, 2009 @03:44AM
from the share-the-juice dept.

An anonymous reader writes "Researchers have developed a way to network household and commercial fridges together in a distributed peer-to-peer fashion that lets them 'negotiate' with each other on the best time to consume electricity. A retrofittable controller is attached to each fridge and then a temperature profile is built around the unit. The controller enables communication between other fridges on the network and also the power source. It enables fridges to work together to decide when to cool down, and thus consume power, based on how much surplus power will be available, and to anticipate power shortages and change their running schedules accordingly to use as little power as possible during these times."

Fridges are fairly low power devices with naturally random and uncorrelated cycling. One would think that in any given neighborhood, the normal randomness of the many fridges' cycling would be sufficient to result in a fairly level electrical "base load". I can't see that enforcing the levelness of this distribution could actually offer very much of a reduction in the peak load on the grid. What causes excessive peak loading is the coordinated use of many high-power loads. Typically this is air conditioning in the summer - all the units run simultaneously because it's hot outside, and each unit draws about 50 times more power than a fridge. Clothes dryers and washing machines in the evening also do this to a lesser extent. In the grand scheme of things, I really don't think there's much room for improvement through load-leveling of just fridges.

This probably isn't pitched at householders. I think it would be great for supermarkets, cold warehouses, booze shops, chemical plants etc... people who need commercial/industrial levels of refrigeration.

You would be surprised. A lot of people keep a second fridge (or, more often, a second freezer) in their garage or basement. There are also small "dorm" fridges that people use to keep beer, soda, whatever handy.

Imagine you have a wind generator on your roof and several appliances connected. If the generator can't power all the devices simultaneously then they could negotiate with each other to smooth out the demand.

eg. If I put the kettle on to make a cup of tea the fridge could switch itself off for a couple of minutes. If I step in the shower all power can be diverted to the water heater, etc.

On a larger scale, smoothing out the demand could avoid building power entire power stations. This probably won't happen for the next 100 years, but one day it will.

Fridges as we know them are pretty sad contraptions with no shortage of room for improvement [typepad.com]. They put a whopping big heat source under the chamber they're trying to keep cool. They use room air from the hottest part of the house, even though in most homes that room is a foot or two away from outside air that is much cooler, if not actually even cooler than the fridge interior should be. In general, they're an agglomeration of kluges and marketroid idiocies. So yeah, this could be a key part of a rethinking of what a fridge is and how it works that could eventually cut power usage by as much as eighty to ninety percent. The same could be said of quite a lot of appliances and HVAC components. Hell, done right, we now know that comfortable homes can be built that require no conventional heating or cooling systems at all [nytimes.com].

Kinda makes you wonder why we're supposed to need this "smart grid" for all this massive increased demand we supposedly have no way to avoid, doesn't it?

Humans are not random operators, especially in industrialized societies. Spikes can come in as little as fifteen to twenty seconds in a society like ours. Rush hour starts and within fifteen minutes you starts seeing a wave spreading away from centers of workplaces of air conditioners being turned on or up and lights going on as people get home. The Superbowl starts and everybody comes indoors from the barbeque to watch the game, air conditioners get turned up as the patio doors get shut. Ad breaks come and toilets all across the area flush within thirty seconds of each other all over the time zone. A big audience tv show has whispering or something else quiet and air conditioners get turned off so people can hear what's on screen.

We live in a society where most people get up around the same time, go about the same distances, stay away for about the same durations, and come back in to do the same damn things as big chunks of their neighbors for hundreds of miles around. And some of these things, like rushes during ad breaks or when a popular show ends have noticable peaks and drops that can be measured in tens of seconds. This doesn't even get into things like what happens when all the living soil is replaced with pavement and, for example, stormwater load spikes get much higher and then drop off much faster. And then, with all that water moving faster everywhere, again more people turn devices on and off to deal with the consequences.

What's your point? There are thousands of things that people "could" do that they don't. They could superinsulate their homes with dirt, straw, and a few weekend days. They could teach their kids the basics of astronomy in an afternoon or two. They could all show up at the polling place and vote for every single election. Hell, we could all build cantennas and have free wireless in every city in the world by the end of this week.

Reality isn't about what people in theory could do. It's about what they will do. And out here in the real world less than one percent of the population has the skills to do what you're suggesting and less than one percent of that one percent actually might. No comparison to a plan like this, not even taking into account the fundamental issues of determining protocols and load calculations.

Living in Canada where it is -25 outside right now, I have always found it an extreme waste of energy to be powering a fridge and freezer to keep things cold in a house I am paying out the nose to heat because it is so cold outside for 1/3 of the year or more.

How come new houses aren't built with some kind of a "chill pipe", kind of like an insulated duct line that routes outside air directly into the kitchen, that could be connected to the fridge? The pipe could be automatically closed or opened as the fridge detected the temperature outside.

That seems like energy conservation taken to a ridiculous extreme to me.

A model like this means that the people who use the most power pay for the production of those new energy generation facilities that you love so well, while those able to curtail their energy usage are rewarded by being charged less. It is essentially the only logical model. When we build a power plant in the USA, it costs ALL taxpayers some money, even if we live off-grid, because of bullshit subsidies and other nonsense.

Um, they have exactly that... The PP was just being flamebait. Of COURSE you wouldn't want lights being turned off on you when you are in the room.

But here is the deal.... You really don't want someone else telling you when you can run your own stuff. What you want is things like "we have a peak load time, do what you can to conserve" and YOUR controller starts taking measures to do extra conservation based on your individual needs. Likewise, "we have a surplus, rates are lower right now" so run the dishwasher, etc. You can also do some time-sliced sync of compressors (not just fridges, but AC units too, but if you look at this on a grid-wide basis it's going to even out anyway. Better is to let your fridge warm a couple extra degrees (if your situation allows) during peak load times (not running AT ALL for a while.)

Going forward, we all need to do what we can to save / manage energy more efficiently. Let's use alternative energy sources "green power" to cut down on legacy power generation, cutting pollution, while at the same time cutting energy consumption to reduce need for legacy power even more.

There are real, and hard, limits on how efficient you can make them - most installed refrigerators are going to have to fit into a standard slot. Increasing insulation means losing internal capacity, and remodeling a kitchen to increase the size of the 'slot' is expensive even where practical.

To be honest, I tend to worry a lot less about energy conservation in my home in the winter, since I've got a big machine in my basement dedicated to burning methane for the sole purpose of producing heat.